Befbigebating-machine



J. D. ROSS.

REFRIGERATING MACHINE.

APPLmATloN msn SEPT. e. 19:3.

2 SHEETS- SHEET l.

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Jaw/E5 /POJJ AnaB/vers Patented Aug. 22, 1916.

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J. D. ROSS.

REFRIGERATING MACHINE.

APPLICAHON FILED SEPT. 6. |913.

Patented A110. 22, 1916.

2 SHEETS-SHEET 2.

wpd ULg/3 ATTORNEYS JAMES D. ROSS, 0F SEATTLE, WASLHINGTON.

nEFBIGEnATING-MACHINE.'

Specication of Letters Patent. Patented Allg".4 22, 1916.

Application led September 6, 1913. Serial No. 788,390.

To all whom it may concern.'

Be it known that I, JAMES D. Ross, a citizen of the United States, and aresident of Seattle, in the county of King and State of Washington, haveinvented a new and Improved Refrigerating-Machine, of which theIfollowing is a full, clear, and exact description.

This invention relates to refrigerating systems of that type wherein thecooling is effected by the evaporation of a liquefied gas or theexpansion of a compressed gas.

At the present time the only eflicient refrgerants are very offensive,and in some instances poisonous, and heretofore it has been practicallyimpossible to design and install a refrigerating system adapted for usein residences and business places because of the constant attentionrequired to maintain the system gas-tight. i

lt is one of the objects of the present invention to provide anextremely simple, durable and efficient refrigerating system whichautomatically maintains a substantially uniform temperature and whichdoes not require the care of an attendant except only occasionally forthe purpose of inspection to see that the apparatus is operating atvitsbest efciency.

The place where leakage is most serious in present systems is at thepump or compressor, and to overcome all chances ofleakage the presentsystem contemplates the complete incasing of the pump and means foroperating the same, so that there is positively no leakage of gas. Thepump maybe of reciprocating or centrifugal type, and the shaft thereof1s preferably connected with the rotor of an induction motor. The pumpand rotor of the motor are incased, and the sulfur dioxid, ammonia orother refrigerant is free to pass to the chamber inclosing the rotor,but leakage from such chamber to the atmosphere is absolutelyprevented.The inclosing casing for the motor may be so designed as to include thestator as well as the rotor, as the refrigerant is anhydrous, and

consequentlyrusting of the machine will notl take place, and thewindings for the rotor.

lcan be suitably protected to withstand theefi'ect of the gas.

Another object of the invention is the provision of simple and effectivemeans for controlling the starting, stopping and running of the motor insuch a manner that the system' will maintain a practically unl- .formtemperature in the chamber or building intended to be cooled, therebeing used 1n connection with the motor controlling means, a dev-ice foropening yand closing a flow of cooling water for the condensing coilv ofthe system, so that when the motor is stoppedor started the coolingWater will be cut oil or turned on.

An` additional object is the employment of an aspirator in series withthe centrifugal pump and cooling coil, whereby `the continually pumped.liquid sulfur dioxid, ammonia or other refrigerant, will entrap vaporand draw it out of the refrigerating coil and cause condensation of thevapor by the illtermingling of the latter with the liquid in thecondensing coil.

With such objects in view, and others as will appear as the descriptionproceeds, the invention comprises various novel features of constructionand yarrangement of parts which will be fully set forth in the followingdescription and claims appended hereto.

In the accompanying drawings, which illustrate certain embodiments ofthe invention, and wherein similar reference characters are employed todesignate correspond- `the top or wall of a refrigerator or a room to becooled, there being within the refrigerator' or vroom a refrigeratingcoil B, which has the end 1 connected with a condensing coil 2 and theother end 3 connected with an aspirator C. A pipe 4 leads from the pipe1 at a point between the coils B and 2 to a centrifugal pump D, therotary element 5 of which 1s secured to a'shaft 6 thatis driven 'by aninduction motor E, The rotor 7 of the inductionfmotor is secureddirectly to the shaft 6, which latter is journaled in bearings 8 and 9.Surrounding the rotor is a stator 10 having energizing windings 11. Thepump D is provided with a gas-tight casing 12 and the rotor 7 isinclosed in a gas-tight casing 13.

Both of said casingshave openings 14 and` 15, respectively, throughwhich the shaft 6 u so ' ings 32 .and of the circuit-closing sole-r-noid F, suchwindmgs 32 and 33 being confreely extends. The gaseousrefrigerant is free to pass from the casing 12 into the casing 13, andas the bearings 8 and 9 are disposed respectively in the casings 12 and13, the shaft does not require paclings or stuffing boXes, since suchshaft does not extend through the outer walls of the said casings. Bythis means it is obvious that there is no chance for the refrigerant toescape -into the atmosphere and become a menace to health. Thecentrifugal pump D is of any desired type, so that the details ofconstruction need not be explained; and this pump is provided with anozzle 16 which is disposed within the-chamber of the aspirator C. Thischamber 17 has a conical wall 18 provided with an expanding port ornozzle passage 19, and the contracted tip of the nozzle 16 is disposedclose to and in alinement with the port 19. The pump draws the condensedrefrigerant from the condensing coil 2 through the pipe 4,- and thisliquid is discharged through the nozzle 16, which creates a suction inthe chamber 17, and as such'chamber 17 is connected with the vaporizingor expansion coil B, the vapor from the latter is drawn out and causedto mingle with the liquid sulfur dioxid, and is consequently condensedin the coil 2. A contraction or choked passage 20 is pro vided in thepipe 1 at a point between the coil B and branch 4, and the liquid sulfurdioxid under high pressure abruptly eX- pands in entering the coil B,and in eXpansion absorbs heat units from the air surrounding the coil,in a manner well known. l The condensing coil 2, as well as part 0f theaspirator C, is cooled in any suitable manner, as for instance, by beinginclosed in' a chamber 2l through which water flows. This chamber has asupply pipe 22 and a discharge pipe 23, and in the supply pipe is avalve 24 which is adapted to automatically open and close as conditionsrequire. The opening and closing of this valve are effectedsynchronously with the starting and stopping of the motor E, and,furthermore, these operations are accomplished preferably automatically,as by means of a thermostat located in the chamber which is cooled bythe refrigerating system. Hence, as shown in Fig. 1, the cooled chamberis provided with' a thermostat 25 which `is adapted to engage liXedcontacts 26 and 27 at predetermined low and high temperature limits. Thethermostat 25 is connected by a wire 28 with a supply main 29, and the.contacts 26 and 27 are connected respectively tov wires 30 and 31 whichare in turn respectively connected wlth the sections or windnected by awire-34 with the other supply main 35. The solenoid F has a core 36 thatcarries a bridging contact 37 adapted'to engage contacts 38 and 39. Thecontact 38 is connected with the supply main 29, and the Y v theinduction motor E. The other terminal of the iield windings of the motoris connected by a wire 41^with the supply mains 35. When the temperaturein the cooled chamber rises, the thermostat 25 engages the contact 27and current then flows through that circuit -in which the winding 33 ofthe solenoid is included. The circuit closer for the motor isconsequently closed so that the motor will start and cause therefrigerant tov be pumped through the system. When the cooled chamber islowered in temperature to the required limit the thermostat 25 willengage the contact 26 and thereby close the circuits in which thewinding32 of the solenoid is included, such winding causing the motor circuitcloser to be opened, so that the pump will be stopped. The contacts 26and 27 are connected respectively by wires 42 and 43 with sections 44and 45 of the currents will not be set up therein, but if a conductivematerial is used it should be of such high'resistance that the lossesdue to eddy currents will be practically m7.

In Fig. 2 a modification is shown with respect to the pump D between thecondens- Y ing coil 2 and refrigerating coil B. The pump is shown as amulti-stage centrifugal pump which serves to cause an effectivecirculation of the liquid and gaseous refrigerant without need of anaspirator. This pump is shown diagrammatically, but it is to beunderstood that a pump of any suitable design will be satisfactory.

The modification shown in Fig. 3 resides solely in the use of agas-tight casing or housing 13 for inclosing the-entire motor, that isto say, the rotor and stator. As the refrigerant is anhydrous it has noinjurious effects on the parts of the motor and the coils can besuitably protected so as not to be the invention appertains', and whileI have.

described the principle of operation, to-

' gethe'r with the apparatus which I now con- Sider to'bethe' bestembodiment thereof, I desire to have it understood that the apparatusshown is merelyillustrative, and that such changes may be made whendesired as are within the scope of the appended l claims.

Havinng thus described my invention, I claim as new and desire to secureby Letters Patent:

1. A refrigerating machine comprising a,

condensing coil, an expansion coil, an-ex pansion means between thecoils for causing the refrigerant to expand, in entering the coil,-apump having its suction e expansion side connected between the .saidmeans and condensing coil, an aspirator between the e delivery sideofthe pump and the condensing coil, and a connection between the eX-'pansion coil and aspirator wherebyI the lat- 25 ter draws o thelexpanded gas from' the` former. I 2. A refrigerating machine comprisinga condensing coil, an expansion coil into which refrigerant from thecondensing coil eX- pands, a rotary pump connected with both coils, andan aspirator connected with the discharge Lend of the expansioncoil andreoei-ving' end of the condensing coil, and also connected withthe pump,whereby the iiuidl discharged from the latter will draw the expandedgasl from the-expansion coil.

Inv testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses. y

JAMES D'RQSS. Witnesses: l i

W. J. MGKEEN,

L. H. Rosie.

